Photographic electric lamp



P 1931. w. R. GRUBER PHQTOGRAPHIC ELECTRIC LAMP Filed Dec.- 17, 1929 INVENTOR I iii/1241 11? GFuler The complete device includes. a p

' Patented Sept. 15, 1931 WILLIAM R. GRUBER, OF NEW YORK, N. Y.

PHOTOGRAPHIC ELECTRIC LAMP 'Applieatiorr filed December 1 7, 1929. Serial No. 414,673.

I This invention. relates to lighting devices and more" particularly to electric lamps of the arc type-as used in photography.

Such lamps are necessarily compact for portability, easily operated, safe. in use and must produce powerful rays of actinic light instantly upon demand.

It is therefore an object of this invention to provide a device capable offu-lfilling the foregoing requirements andwhich can be operated by the usual current supplied for incandescent lamps.

A further feature is in the provision of a small lamp, telescopically fol dable to fit the average pocket, and when extended to present a handle by which the lamp may be conveniently manipulated.

Another purpose is to produce a lamp composed of few and simple parts, not easily. disarranged nor subject to excessivewear.

These several advantageousobjects are accomplished, by the novel construction and combination of parts hereinafter described and shown inthe accompanying drawings,

" 25 forming an essential part of this disclosure,

and in which I Figure 1-is a perspective view of a complete embodiment of the invention, illustrating its'a'ppl'ic'ation.

t Figure 2 is a longitudinal sectional view of the lamp as in shortened or compacted condition.

Figure 3 is a similar view of the same as extended at full length.

' Figure 4 is a transverse sectional view taken on line 4=4 of Figure 3 drawn to an enlarged "scale.

Figure 5 is a similar sectional view-take on line 5-'5 of Figure 3.

lug 10 adapted to engage with any commercial type of electric outlet, as the wall socket 11, preferably set in the base-board 12'close.to the "floor 13.

A conductor 14 leads to a resistance coil 'havin" a perforate casing -15-mounted on "supports 16 capable of being folded closely over the casing when not extended for use.

Leading from the coilis a conductor 17, 50 of any desired length, to acommercial switch 18 operated by an extending lever 19 into off and on positions.

1 he switchhas a cylindrical stem 20, in the upper recessed end of which is fixed a tube 21 of conducting material in circuit with one oi" the poles of the switch by a conductor 22, and passing out through an opening 23 in the tube is a conductor 2a connecting with the other; pole of the switch.

Fixed on, the switch stem is a circular flanged head 25 and, set firmly withiuthe flange is a plain cylindrical casing 26 of dielectric material, such for instance as indurated fiber, having set in its upper end, which projects above the bushing 28, a similar but smaller, reversed head 27.

, Mounted centrally in the head 27 is a non conducting bushing 28 having a flanged upper portion to seat on the outer surface of thehead and provided with a key 29 to prevent rotation.

The bushing is-rigid on the tube 21 acting as a limitstop for its descent, while the upper end of the switch 18 limits, the upward movement of the tube as will later be seen.

Fixed on the interior of the dielectric casing 26-, which answers the purpose of a handle in manipulating the instrument, is a nonconducting block 30 provided on its inner side with a spring contact 31 terminating just belowthe head 27 and connected by a binding screw 32 with the conductor 24.

. -The u-pperportion of the tube 21 is split and slightly inbent to act as jaws for frictionally engaging a carbon rod 33 neatly fitting the tube but adjustable therein.

A semi-cylindrical metallic shell 34, is conformably slidable over the casing 26 to rest uponv the flange of the lower head 25 when the device is collapsed, and may be extended,;as in Figure 3 when in operation.

' The side edges of the shell are formed into open beads 35 which extend only partially the length of the sides to enclose more than half the circumference of wire rods 36 which constitute. the vertical elements of a curved rectangular frame 37, one of the lower ends ,38 of; which is bent inwardly and then downwardly to pass through an opening 39 in the-headi27 and engage the contact 31 when in operative position. The frame normally rests on the outwardly flanged portion 34 of the lower full circumferential end of the shell 34, and it is to be noted that the frame wardly reaching flange to engage the shell and partially supported at the front by a semi-circular band 42 formed on the upper end of the shell 34. a e

The upper part of the member4l is provided with an annular corrugation 43, above which is a split sleeve 44 to frictionally engage an upper carbon 45 disposed axially of the apparatus in alinement with the mating, lower carbon 33.

Current is conducted to the lower carbon 33 directly from the switch by the conductor 22, and tube 21, and to the upper carbon 45, from the switch 18, conductor 24, spring contact 31, frame elements 3839 to! the frame and thence to the cover 41 in which the carbon is adjustably held.

In operation the upper and lower portions of the device are drawn into the position shown in Figure 3; thereafter current is turned on and the switch raised or pushed inwardly as far as it will go, bringing the carbons 33-45 into contact and forming a circuit therebetween.

Upon slightly separating the carbons, by withdrawing the switch, an arc will be formed between their points and a light obtained, the rays of which pass through the screen 40.

When the switch is fully withdrawn the bushing'flange will seat on the head 27 and the carbons so widely spaced as to break the circuit.

To collapse the device into its smallest compass, for portability, the screen and frame are raised, out of the guides 35, inverted and replaced as seen in Figure 2, in which position the upper carbon is obviously withdrawn.

' In order to avoid entanglement or breaking of the conductors 2224 relative rotary motion of the parts is prevented by the key 29 at all times.

As changes of construction could be made within the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described the invention, what is claimed as new and desired to secure by Letters Patent, is

1. An electric lamp comprising a dielectric casing having heads at both ends, a shell slid able over said casing, said shell being partial= ly open at one side,a screen slidably engaged with said shell to cover the opening therein, a cover over said shell, means on said cover to frictionally grip a carbon, a dielectric bushing slidable in the inner of said heads, a switch having a stem slidable in the outer head, a tube fixed in said tube to rigidly engage said bushing, means in said tube to frictionally grip a second carbon, and electric connections between said switch and each of said carbons.

2. An electric lamp comprising a cylindrical non-conducting casing having metal heads at its oppositeends, a semi-cylindrical shell having parts to telescopically engage over said casing and containing an opening in its side wall, a screen carrying frame slidably engaging beaded edges on said shell, said frame being reversible, means at the outer end'of said shell to carry a carbon, a tube slidable through said heads carrying a second carbon, means for limitedly adjusting said carbons, and means to produce a circuit therethrough.

3. An electric lamp comprising a two part collapsible container arrangedtelescopically,

- each part carrying an electrode one of which is substantially fixed and the other adjustable thereto, means to limit the normal movement of the adjustable electrode with respect to the fixed electrode, said electrodes being electrically insulated from each other, means for conducting current to each electrode, and means to control the circuit therethrough.

4. An electric lamp comprising a two part collapsible container arranged telescopically, each part carrying an electrode one of which is substantially fixed and the other adjustable thereto, means to limit the normalmovement of the adjustable electrode with respect to the fixed electrode, said electrodes being electrically insulated from each other and arranged to produce an arc in the container part carrying the fixed electrode, a reversible screen fittedto cover an opening in said part, an electric conductor for each electrode, and means to control the circuit through said conductors.

5. In an electric lamp using carbon electrodes, a telescopic casing composed of two members, respectively a handle and a screen carrying shell, said handle being dielectric and provided with fixed heads carrying one electrode, means in said shell to carry the other electrode, and means for conducting an electric current to each of said electrodes simultaneously.

6. In an electric lamp using carbon electrodes, a casing composed of a hollow dielectric handle and a shell telescopically engaged therewith, said shell having a lateral opening, a screen slidably and removably engaged with said shell over the openings, an axial electrode adjustably carried by said shell, heads fixed in the ends of said handle, a switch having a stem slidable in the outer of said heads, a bushing slidable in the inner head, means to prevent rotation of the bushing, a tube fixed in said stem and bushing, an electrode frictionally held in said tube, and conductors from said switch to each of said electrodes.

7. In an electric lamp using carbon electrodes, the combination with a two part telescopic casing each having an electrode, of a switch having a stem slidable in one of the casing parts, a split metallic tube fixed in said stem to frictionally receive the electrode therein, an insulated spring contact fixed in the same casing part, conductors from said switch to said tube and contact respectively, means to prevent relative rotation of elements in said part, and means to conduct current from said contact to the other of said electrodes.

8. In an electric lamp using carbon electrodes, the combination with a tubular dielectric handle, a metallic shell slidable thereover, said shell havin an open side, a conducting frame slidabIy engaged with said shell over the opening, an electrode carried 4" centrally by said shell, a second electrode carried by said handle in alinement with the first electrode, means to conduct current to said second electrode, other means to conduct current to said frame, and means to control the current carried by said handle.

In testimony whereof I afiix my signature.

WILLIAM R. GRUBER. 

